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How Much Mold in a Crawl Space Is Acceptable? (Plus 6 Steps to Prevent It)

How Much Mold in a Crawl Space Is Acceptable? (Plus 6 Steps to Prevent It)

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Mold is a common problem in closed places, but how much mold in a crawl space is acceptable?

Actually, it’s not acceptable to have mold in your crawl space. Mold spreads rapidly, which means that a small amount will still cause problems.

Keep reading for more about the causes, symptoms, prevention methods, and removal of mold.

How Fast Can Mold Grow In a Crawl Space?

Given the right conditions, mold can grow rapidly in a crawl space. Don’t be surprised to see mold appear and spread in just a couple of days.

With little exposure to sunlight, crawl spaces are closed areas that are typically humid, dark, and warm. That way, they have the ideal conditions for mold to grow.

How Common Is Mold in Crawl Spaces?

Mold is a common sight in crawl spaces as they have all the necessary conditions for its growth.

However, it’s not a problem to be ignored. You need to act fast to remove mold from your crawl space.

5 Main Causes of Mold in a Crawl Space

There are several causes for mold growth in a crawl space. Interestingly, they all boil down to moisture in some way or another. Here’s a list of the most common causes:

1 – Cracks In the Foundation

Even the tiniest crack in the foundation wall’s concrete can pose a threat. Indeed, these small hairlines don’t necessarily mean that your house isn’t sturdy enough.

The size of these cracks can allow moisture into your crawl space. The presence of moisture creates the ideal environment for the mold to thrive.

2 – Moist Soil

Most crawl spaces have unfinished floors, meaning that they stand on the soil underneath the house.

Such natural soil makes your crawl space more prone to moisture. It develops mold considerably faster than other houses.

3 – Ventilation

Some crawl spaces, especially older ones, have vents to allow the circulation of fresh air. The problem with these vents is that they don’t filter the air.

Vents usually allow humid air into your crawl space. This leads to the accumulation of moisture, which in turn causes mold.

4 – Leakage

Inspect the pipes in your crawl space regularly for leakage. If any pipe leaks, the moisture level in your crawl space will certainly increase.

This excess water can cause the rapid spread of mold. Sometimes, it can all happen before you know it. That’s why we recommend that you do the inspection even before you see the signs.

5 – Flooding

If you live where it regularly floods, your crawl space may be more prone to moisture. Flooding water can increase the moisture level in the soil around your crawl space.

Therefore, if your crawl space is in a flooding area, you should clean and drain the place right after every flood. Remember, mold spreads rapidly, so act fast.

Is Mold In a Crawl Space Dangerous?

Mold can be incredibly dangerous on all levels. For instance, here are three main causes for concern:

1 – Suffocating Odors

Even though the mold is confined to your crawl space, it still affects every room of the house. Mold spores in your crawl space can spread bad odors throughout the entire house.

Perhaps, a horrible odor doesn’t sound that problematic, though it’s not as easy as you might think. The mold’s musky smell can only be removed if you get rid of the mold itself.

2 – Health Issues

Mold can lead to several health problems. They can range between allergies and severe respiratory issues.

Generally, mold spores affect the nose, throat, and lungs. Therefore, the risk is significantly higher for people with asthma or weak immune systems.

3 – Wood Damage

Mold can damage wood, carpets, walls, and almost everything in your house. Despite growing in the crawl space, the effect of mold still reaches the items inside your home.

In addition, wood damage can weaken your foundation. This can cause a serious problem in the long run.

5 Signs Your Crawl Space Has Mold

So how do I know if I have mold in my crawl space? Fortunately, there are some tell-tale signs that indicate the growth of mold in your crawl space:

  1. A musty smell comes out of your crawl space
  2. Increased allergies and respiratory problems affect the residents of the house
  3. Visible signs of mold show on the floors
  4. The house’s wooden floors get warped
  5. Rot appears on the house’s wooden structure.

Can You Sell a House With Mold In a Crawl Space?

Well, yes but you don’t want that!

No law prevents you from selling a house with a moldy crawl space. Yet, mold decreases the value of your house drastically.

Moreover, some areas enact laws requiring homeowners to inform buyers about any previous or current mold problem.

Even if you don’t tell, the inspection done by the buyers will surely tell of any mold issues.

3 Steps to Remove Mold From Crawl Spaces

When you discover mold in your crawl space, you can either contact a professional or do the job yourself. Getting rid of mold can be hard and dangerous, so if you choose to go for it yourself, follow these steps:

1 – Wear Protective Gear

You shouldn’t contact mold without wearing protective gear. Choose OSHA-approved equipment.

The protective gear includes:

  • Goggles
  • A respirator
  • Gloves

In addition, you should wear clothes and shoes that you’ll throw away after the task. You don’t want to spread the mold further via your clothes or shoes.

2 – Spray the Mold

After you identify the location of the mold spores, spray it with a mold-killing formula. You can also use some cleaning material, such as borax or bleach, if your problem isn’t so severe.

Wait for the sprayed area to dry and remove the mold with a scrub brush. Make sure you get every bit of mold in your crawl space.

3 – Address the Cause

If you only remove the mold, it’s more likely to reoccur. Therefore, if you want to eliminate the problem altogether, identify and address the main cause of the issue.

Check for foundation cracks, leaky pipes, or damp soil to eliminate the root cause. This way, you can prevent the mold from regrowing into your crawl space.

6 Methods to Prevent Mold in a Crawl Space

Fortunately, there are several ways to help prevent mold growth in the first place, including:

1 – Gutter Cleaning

If your gutters get clogged, the water may spill out on the soil around your house’s foundation. This way, it gets into your crawl space, raising the moisture level.

With excess water in and around the foundation of your house, your crawl space is more prone to growing mold.

2 – Drain Tile Systems

Drain tile systems are an effective method of controlling the moisture level underneath your house.

These systems direct the water to the drainage, thus away from your crawl space. The drier the place gets, the safer it is.

3 – Yard Grading

Sometimes, the yard slopes toward the house. This means that any water in your yard eventually flows into your house’s foundation.

Re-grading your yard can solve this problem and prevent the water from getting into your crawl space.

4 – Downspout Extensions

Increase the length of the downspout drainage. Short downspouts discharge water near your foundation.

This released water dampens the crawl space, increasing the moisture level around your house. Such dampness is the main cause of mold in your crawl space.

5 – Encapsulation

It can be quite efficient to encapsulate the floors and walls of your crawl space. Covering the entire area with special material can prevent the accumulation of moisture.

That way, the water in your yard or soil won’t get inside your crawl space. Ultimately, this would eliminate the mold problem.

6 – Installing a Dehumidifier

A dehumidifier can be a great prevention method. It’s especially beneficial if you live in a humid area as it decreases the humidity level.

This appliance relieves the causes of asthma and allergies. It’s advisable to install a dehumidifier if you live in a flooding area.

Final Thoughts

So, how much mold in a crawl place is acceptable?

In fact, the tiniest amount of mold in a crawl place can’t be acceptable. Mold is a major issue that requires fast action.

Unfortunately, mold growth can be rapid and uncontrollable. Therefore, we recommend that you prevent the problem before it occurs.

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